Photoemission deep in the SrTiO 3(001) band gap is found to be ubiquitous in bulk crystals and epitaxial films for all doping levels. Such features are present even when there is little signal near the Fermi level. This result challenges earlier conclusions about deep features being derived from the metallic band associated with free carriers. Rather, our data point to these states resulting from interstitial oxygen and its interaction with donor electrons.